Vertically shiftable platform support for office furniture



March 3, 1953 F. s. SCHADE 2,630,359

VERTICALLY SHIFTABLE PLATFORM SUPPORT FOR OFFICE FURNITURE Filed March21. 1950 2 SHEET S--SHEET l INVENTOR tions, and the like.

referring to the record sheets in the files.

Patented Mar. 3, 1953 VERTICALLY SHIFTABLE PLATFORM SUP- PORT FOR OFFICEFURNITURE Frank Stanley Schade, Holyoke, Mass., assignor to NationalBlank Book Company, Holyoke, Mass., a corporation of Massachusetts QApplication March 21, 1950, Serial No. 150,924

1 Claim. 1

This invention relates to a vertically shiftable platform support foroffice furniture such as a .tray support for an office work stand of thetype adapted for holding and handling bulky record files.

Large business and governmental offices usually have various types ofvoluminous and bulky records for a variety of bookkeeping transactions,personnel dispositions or administrative regula- Such records are keptsystematically indexed and classified and generally for handlingpurposes are stored in such a way that a group of records may be removedfrom the location of storage to be carried to a work location whereentries can be made or the record sheets otherwise referred to. In manyfiling systems the records may be permanently stored in portable traysof various types and in other systems groups of files may be assembledfrom their permanent locations on carrying trays and transported to aworking station as near a desk or other working area. It is also commonin working with such files for an office worker to alternately stand andsit for certain periods while An object of this invention is to providea device to assist in expediting the handling of this type of ofiicework.

To illustrate more specifically, a clerk may be working at his desk witha particular set of records. The records may be held on a work stand orother movable support near the desk at a convenient height. Havingcompleted the desk work,

- the clerk then finds it necessary to do reference 'or tabulating workwith the same set of records at filing cabinets.

For efficient handling the records should then be at a different heighton the stand for reference and checking at a convenient reading level orfor making appropriate entries. The device of this invention isaccordingly designed to provide a readily adjustable mechanism toaccomplish a change in working level with a minimum of inconvenience andeffort. It is easily manipulated to raise or lower the supportingsurface for record files with practically no interruption in the work athand.

Another object of the invention is to provide a device readily adaptedfor mounting on a general utility work table of a type commonly used inmany offices.

A further object is to provide a device having a counterbalancedparallel linkage system by means of which the supporting platform mayeasily .be shifted upwardly and downwardly with a comparatively heavyload of record files.

in intermediate and lowered positions;

A still further object of the invention is to provide a device adaptablefor use in an enclosed cabinet stand whereby records may be made readilyaccessible from a place of concealment as desired and also may beprovided with an individual permanent or semi-permanent depository.

Other objects and advantages of the invention will be seen from thefollowing description and accompanying drawings- Inthe drawings:

Fig. 1 is a side elevation with various parts in section of a workstand'with the new device mounted on the stand and supporting a recordfile tray in elevated position;

Figs. 2 and 3 are similar views of the device Fig. 4 is a sectional viewonline 4'4 of Fig. 1; Fig. 5 is a side view of a modified constructionof the device as adapted for a cabinet stand apparatus and illustratedin elevated position;

Fig. 6 is a section of the cabinet stand of Fig. 5 with the device inlowered position and a lid covering the cabinet top; and

Fig. 7 is a perspective view showing a removable tray clip as used onthe platform of the device.

A general utility work stand or table of the type adapted for use withthe new device is a familiar piece of oflice equipment. In theparticular form of stand here shown in the drawings it is provided witha fiat top I having a longitudinal recess 2. Theside walls ofthe-recessare cut away ,at their mid-portions to provide slots as at 3.A central opening 4 between i the slots 3 is-alsoprovided in the bottomwall of the recess. The table serves with its particular form of recessto provide a convenient means for removably supporting a variety of worktrays or heavy binders as may be nested on the table with portionsthereof matching the recess. 1

The new platform device embodying the invention is mounted on the tabletop. It comprises a bottom support as lower plate 5, an upper supportplatform as plate 6, and a parallel linkage mechanism connecting the twoplates. Centrally pivoted at the under side of the lower plate 5, as ona rivet 1, is a rotatable swivel lock bar or strap latch 8. When thedevice is placed on the top I with latch 8 suspended in the recess onthe underside of plate 5 directly over the central opening 4, anoperator may reach up from underneath to pivot the latch and swing itsoffset end nesting relation between the sidewalls of the" recess.

The top I of the work stand is itself vertically adjustable by means oftelescoping legmembers 9 and ID. A series of holes l l inthe legs permittheir relative positioning by bolts as at' I2... A bracing shelf l3 andswivel casters M' complete the stand assembly.

It will be seen from a comparison of Figs. 1, 2, and 3 that the upperplate or platform 6 of the new device may be shifted from a loweredposition', resting on the lower plate 5; to an elevated positionvertically" spaced f'rom the lower plate and held parallel thereto atall times by the. linkage mechanism connecting the two plates.

Parallel links l5'and i6, with a toggle joint associated with at leastone of the links, form the connecting structure at the sides of theplates. The'links and It are pivoted at their upper ends to dependingears IT and {8 of transverse straps l9 fixed on the underside oftheupper plate-platform 6"(Figi i). Intermediate the ends of" links l5short toggle links 2d (pivoted atone endas toan e'arZl of a transversestrap 22 fixed on lower plate 5) arepivotally connected as at 23 to formatog'gle joint or knee with link 15. The lowerends-of links l5 extendingbeyond the kneeare pivotally mounted on two complementary'guide membersas slide bars 2e located at opposite side edges of the lower' plate 5.Bars 24' are provided with roller wheels 25 at each endthereof, thewheels being held in runways formed by upstanding flanged sides 25 ofplate 5 (see Fig. 4). The axles of the wheels provide the pivotalattachment of links I5 to the bars.

The parallel links I 6 are similarly connected to the slide bars 24 ofplate 5. Transverse straps 2 1 and 28'-may be mounted for structural riidity between the laterally aligned" pairs of links l5 and I6respectively. A connecting bar 29 joins the lower ends of links l5 andthe axles of wheels 25 adjacent plated. A tension spring 3B is hookedatoneen'd-to'bar 29 and its other end to plate 5 to urge th'e' links l5as showntowardsan in-line position of the toggle joint member's.

When platform 6 is in its lower position (Fig. 3 the links and the slidebars of the device lie ateach side of plate 5 in a straight linecollapsed position. The portion of link l5 forming a toggle joint withlink 2E) lies in adjacent relation withlink' At'their'lowerpor'tions'links l5 (Fig. 4) are offset-outwardly to provideclearance for a nesting relationship. The spring 30 is here under itsgreatest tension.

By lifting platform 6, an operator may cause the same to swing upwardlyof plate 5 and the toggle linkage to unfold (Fig. 2), the bars 24sliding longitudinally in the tracks of plate 5.

' As the platform 6 is movedupwardly it is shifted lengthwise in anarcuate path according to the movement of the parallel linkage system.Links l5= and I6 are carried to a-vertical perpendicular positionbetween plates 5 and 6 and slightly beyond' to an oppositely angledcondition as shown byFig. 1. In this position the guide bars 24 come torest with-the-wheels against stop lugs 3! attached to the flanged sides26 of plate 5. Thus, further movement of the toggle joint to an in-lineposition and the upper plate 6 to a relatively lower position isblocked. In this condition, the platform is held in its elevatedposition of Fig. 1 by the weight of the load on the angled links andendwise pressure of bars 24 against lugs .il. Spring 36] is' alsoexerting tension to maintain the platform in this position.

When platform 6 is in a lowered position (Fig. 3) the links are lockedagainst the action of the spring. The toggle joint is folded at thekneeand. set. in a straight line. The force of the spring is againstlongitudinally aligned pivots 23 I3 and 2|.

The mechanism includes the spring counterbalancing means to assist incarriage of a load on. the platform plate 6 in raising and lowering thesame. The spring 38 is at all times under tension overlying bottom plate5. It is hooked atone end to the bar as and anchored at the other end bya hook in the bottom plate 5 between stop lugs 3|. It will be clear thatoninitially lifting platform (5 the spring tends to draw the lower endsof links I5 around the rising toggle joint pivot of knee 23. Theslidable bars permit a rotative movement of links I5 around the knee andthe action of the spring tends to float a heavy load on the platform 6to its'upward position. In the reverse operation, on lowering theplatform, the spring will counterbalance a heavy load and act to resista toorapid descent of the platform against plated. 1

Platform 6 is provided with upturned flanges 32' and 33' at its side andend edges respectively.

These flanges assist in seating and holding record file trays onthe-platform surfacesuch as atray 3 t illustrated by the drawings. Tray34 is a known type of'machine postingtraynow in commercial use and isprovided with cornered end walls 35 having open sides. Drop bars 36' arepivoted at the sides' for swinging laterally and permitting individualcards of a stack 31 to be offset for bettervisibility and handling.Carrying handle openings 38 are also provided centrally in each end wallof the tray 34.

Platform ii as shown is additionally fitted with holding clips 39 and M]for convenience in mounting a tray in the assembly. Clip 39 at the leftin the drawings may be permanently fixed to platform 6 with its top hookportion overlying that end. Clip as at the other end may be removable.It will be clear that in. fitting tray 34 on the platform the tray maybe tilted to hook the top of clip 39 in the adjacent handle opening 38and the tray then rested on the platform. The removable clip 4t isthenfitted on the other end. Clip id is of spring metal and has a loweroffset portion with an upstanding tongue 4| (Fig. '7) fitting into aslot in the underside of platform 6. The upper hooked portion is firstinserted into the handle opening 38 and the offset tongue is then swungand snapped into-place in the slot. To remove the clip the tongue issprung from its slot by pressure on the rounded top hook portion whichflexes the metal against the lower edge of the handleopening 38 andpermits withdrawal of the clip. Thus the tray 34 may be secured againstremoval and can be handled to raise and lower the platform 6.

The assembly as described provides a sturdy and rugged unit for use inmanipulating heavy record files. It will be clear that the togglejointed parallel linkage mechanism with its spring balanced tension maybe modified in some respects while preserving the advantages of thedevice as disclosed by Figs. 1-4. One such modification is illustratedby Figs. 5 and 6 which show a platform device as used in a safe orenclosed cabinet type of stand.

In this embodiment two parallel links 45 and two short links 46 areprovided for the elevating mechanism. It will be seen that the slide bar41 for the lower ends of the links is mounted on wheels in a track of alower support plate 48 as in Figs. 1 to 4. The device is entirelyenclosed in either position of adjustment by cabinet walls 49 and 50. Inits upper position (Fig. 5) the stop against an in-line position of thetoggle joint is provided by abutment of the platform 5| against thecabinet wall 50. In this example the latch mechanism andcounterbalancing spring have been omitted. The device rests on the fioor52 of the cabinet or the lower support may be an integral part of thecabinet itself. A hinged cover 53 is provided to conceal and lock thefile contents when in lowered position.

In the form of Figs. 5 and 6 the device has special utility in providinga greatly simplified construction for an enclosed cabinet type of file.The walls of the cabinet may be of fire proof construction for overnightand other temporary storage. The desirability of this type of ofiiceequipment is widely recognized for the permanent or semi-permanentdeposit of file records. Confidential files can be immediately concealedand/or made available as desired and without elaborate precautions forhandling.

Having described my invention, I claim:

A vertically shiftable platform device for record file holding equipmentand the like comprising a lower and an upper support, parallel linksbetween said supports and mechanism associated with the links forguiding and supporting said upper support from superimposed collapsedposition to superimposed vertically spaced position in a pathsubstantially perpendicular to the plane of said lower support, andspring means yieldably tensioned to maintain said upper support ineither of said positions, said upper support having depending spacedpivotal connections with corresponding ends of said parallel links,longitudinally slidable members carried by said lower support havingspaced pivotal connections receiving the other ends of said parallellinks, toggle link straps pivoted to said lower suport in the plane ofsaid pivotal connections of the parallel links to said slidable meansand offset therefrom, the other ends of said straps being attached infixed pivotal relation with adjacent parallel links at central portionsthereof, said parallel links being rotatable around said strap ends, thelifting of said upper support above the lower support being guided bysaid straps with said slidable members moving longitudinally of saidlower support, a stop for said slidable members at the end of thesupport, said straps with further movement of said members restricted bythe stop holding the parallel links against further rotative movement inthe same direction and in an over the center relation between thesupports, said spring means including a spring connected between saidlower support and said slidable members and constantly urging the latterto- Wards said stop with the centrally pivoted. parallel links on themembers being biased in the direction of further rotation around saidstrap ends, said parallel links, slidable members, and straps incollapsed position between said supports being in parallel relation andthe pivotal connections therebetween in an in line condition, thetension of said spring on said slidable means tending to maintain saidin line position of said pivotal connections.

FRANK STANLEY SCHADE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,824,822 Kradolfer Sept. 29,1931 2,495,046 Wolters Jan. 17, 1950 2,531,140 Linde Nov. 21, 19502,531,880 Herring Nov. 23, 1950

